Top Flange Protective Cover for Thin Plate Container and Thin Plate Container Provided Therewith

ABSTRACT

A package of a thin plate container  1  is prevented from being broken when vacuum packed. A top flange protective cover for a thin plate container detachable to the top flange which is provided on the thin plate container so as to protrude outward therefrom includes: an outside surface having no edges thereon; and a surface facing the top flange, including: a pair of abutting portions abutting against a flange portion of the top flange, for positioning in one direction; and a pair of fitting pawls abutting against the flange portion in one direction perpendicular to each of the abutting portions, for positioning in the other direction, wherein the protective cover is formed to cover the entire outside surface of the top flange when attached to the top flange. The thin plate container is desirably provided with the top flange protective cover for the thin plate container.

TECHNICAL FIELD

The present invention relates to a top flange protective cover for a thin plate container used to contain, carry and store thin plates such as semiconductor wafers as well as a thin plate container provided therewith, and specifically to the improvement of a top flange.

BACKGROUND ART

A thin plate container for containing a plurality of thin plates such as semiconductor wafers, for carrying and storing, is described in Patent Document 1, for example. Such thin plate container is provided with a top flange to be used for carrying such thin plate-container itself by means of a carrier device. The top flange is provided so as to protrude outward from the thin plate container. Patent Document 1: Japanese Patent Laid-Open No. 2004-214269

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

The thin plate container is often vacuum-packed to keep the inside clean during transportation. In such a case, there is a problem that the vacuum package may be broken by a sharp edge of the top flange.

Means to Solve the Problem

The present invention has been made considering the above-mentioned problem and provides a top flange protective cover for a thin plate container detachable to the top flange which is provided on the thin plate container so as to protrude outward therefrom includes: an outside surface having no edges thereon; and a surface facing the top flange, including: a pair of abutting portions abutting against a flange portion of the top flange, for positioning in one direction; and a pair of fitting pawls abutting against the flange portion in one direction perpendicular to each of the abutting portions, for positioning in the other direction, wherein the protective cover is formed to cover the entire outside surface of the top flange when attached to the top flange.

With the above-stated configuration, when the thin plate container is vacuum-packed and carried, the protective cover is placed on and constrained to the top flange. At this time, the pair of abutting portions of the protective cover abut against the flange portion to secure positioning in one direction, while the pair of fitting pawls abut against the flange portion in one direction perpendicular to each of the abutting portions to secure positioning in another direction. In addition, the pair of fitting pawls engage with the flange portion to constrain the protective cover to the flange portion, with the entirety of the flange portion covered with the protective cover.

The top flange protective cover for a thin plate container is desirably formed in a square dish shape or a circular dish shape which covers the entirety of the flange portion, according to the flange portion of the top flange.

The protective cover is desirably provided with: two slits formed from the circumferential edge to both sides of the fitting pawls to facilitate bending of the corresponding fitting pawls; and handles each disposed between the peripheral portion of the protective cover defined by the two slits and the corresponding fitting stopping pawl, for opening and closing the corresponding fitting pawls.

With the above-stated configuration, the fitting pawls can easily bend owing to the two slits and engage with the flange portion. Furthermore, the handles enable the operator to easily open and close fitting pawls just by opening and closing the handles by inserting both hands.

The thin plate container is desirably provided with the top flange cover for a thin plate container. It is also desirable that fitting portions are provided on each of the four sides of the flange portion of the top flange, and fitted portions are provided at two locations at either one of or four locations at both of the pair of abutting portions and the pair of fitting pawls.

With the above-stated configuration, the fitting portions of the flange portion of the top flange fit with the fitted portions at the pair of abutting portions or the pair of fitting pawls, to position the protective cover with respect to the top flange.

EFFECT OF THE INVENTION

As described above, the thin plate container in accordance with the present invention provides the following effects.

While the pair of abutting portions and the pair of fitting pawls on the protective cover are positioned in a state to abut against the flange portion, the pair of fitting pawls engage with the flange portion to constrain the protective cover to the flange portion, the protective cover can be easily attached to the flange portion, and further, during vacuum packing, the vacuum package can be prevented from coming into contact with a sharp edge of the top flange and being broken.

Since the handles enable the operator to easily open and close fitting pawls just by opening and closing the handles by inserting both hands, the fitting pawls can easily bend and engage with and disengage from the flange portion, and the protective cover can be easily attached to the flange portion.

Since the top flange is covered with the protective cover when the thin plate container is vacuum packed, and the profile of the outside surface of the protective cover is formed to have a smooth slant, the vacuum package is prevented from directly coming into contact with the top flange and the protective cover having a smoothly-slanted profile is enclosed in the vacuum package from outside, thereby preventing the vacuum package from being broken.

Since the fitting portions of the flange portion of the top flange fit with the fitted portions at the pair of abutting portions or the pair of fitting pawls, make positioning of the protective cover with respect to the top flange, the protective cover can be easily attached to the top flange.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a protective cover attached to a top flange in accordance with an embodiment of the present invention, as viewed from the underside.

FIG. 2 is a perspective view showing a thin plate container in accordance with an embodiment of the present invention.

FIG. 3 is a back view showing a thin plate container in accordance with an embodiment of the present invention.

FIG. 4 is a perspective view showing a thin plate container with its lid unit and top flange removed, in accordance with an embodiment of the present invention.

FIG. 5 is an enlarged view of a main portion of a top flange in accordance with an embodiment of the present invention, viewed from the rear face.

FIG. 6 is a perspective view showing a top flange in accordance with an embodiment of the present invention.

FIG. 7 is a perspective view showing a top flange in accordance with an embodiment of the present invention, viewed from the rear face.

FIG. 8 is a perspective sectional view of a main portion of a top flange attached to a thin plate container in accordance with an embodiment of the present invention.

FIG. 9 is a perspective view showing a top flange attached to a thin plate container in accordance with an embodiment of the present invention.

FIG. 10 is a side view showing a protective cover attached to a top flange in accordance with an embodiment of the present invention.

FIG. 11 is a perspective view showing a protective cover attached to a top flange in accordance with an embodiment of the present invention.

FIG. 12 is a plan view showing a protective cover in accordance with an embodiment of the present invention.

FIG. 13 is bottom view showing a protective cover in accordance with an embodiment of the present invention.

FIG. 14 is a side view showing a protective cover in accordance with an embodiment of the present invention.

FIG. 15 is a sectional view along arrows A-A in FIG. 12.

FIG. 16 is a sectional view along arrows B-B in FIG. 12.

FIG. 17 is perspective view showing a thin plate container in accordance with a variation example.

EXPLANATIONS OF REFERENCE NUMERALS

-   -   1: Thin plate container     -   2: Container body     -   2A, 2B, 2C, 2D: Side wall portions     -   2E: Bottom plate portion     -   2F: Opening     -   5: Top flange     -   9: Reinforcement rib     -   25: Flange portion     -   25A: V groove     -   26: Main unit portion     -   27: Sliding support means     -   28: Fitting means     -   29: Guide rail     -   30: Supporting portion     -   31: Sliding portion     -   33: Fitting projection     -   34: Fitting pawl     -   34A: Distal-side fitting pawl     -   34B: Proximal-side fitting pawl     -   36: Abutting portion     -   37: Supporting bar portion     -   38: Abutting portion     -   39: Supporting bar portion     -   41: Protective cover     -   42: Abutting portion     -   43: Fitting pawl     -   43A: Pawl portion     -   44: Handle     -   47: Protective cover

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to the attached drawings, an embodiment of the present invention is described below. A thin plate container in accordance with the present invention is suitable as a container used in processes of containing, storing, transporting, and producing thin plates such as semiconductor wafers, storage disks, and liquid crystal glass substrates. The present invention relates to a top flange cover for a thin plate container and is applicable to the entire thin plate containers provided with a top flange. Therefore the description of this embodiment centers around a top flange and a top flange cover, exemplifying the outline of a thin plate container.

As viewed in FIGS. 2 to 9, a thin plate container 1 in accordance with this embodiment includes a container body 2 to contain a plurality of semiconductor wafers (not shown), two groove plates (not shown) each disposed on the side walls opposing each other inside the container body 2 for supporting a plurality of semiconductor wafers contained in the container body from both sides, a lid unit (not shown) for closing an opening of the container body 2, a top flange 5 held by an arm portion of a transport device (not shown), and a carrying handle (not shown) used by the operator for hand-carrying the thin plate container 1.

As viewed in FIGS. 2 and 3, the container body 2 is formed in almost a cubic shape. The container body 2 is in a vertical posture state (semiconductor wafers are placed in vertical posture), and include four side wall portions 2A, 2B, 2C and 2D which serve as surrounding walls, a bottom plate portion 2E and an opening 2F provided above them. The side wall portions have reinforcement ribs 9. The container body 2 is accurately placed in a horizontal posture (semiconductor wafers are placed in horizontal posture) on a placement table when mounted opposing to a wafer carriage robot (not shown) in a manufacturing line of semiconductor wafers. The side wall portion 2D, which serves as the bottom portion when placed in horizontal posture, is provided at its outside with a main unit positioning means (not shown) of the thin plate container 1. The side wall portion 2B, which serves as the ceiling portion when placed in horizontal posture, is detachable at its outside with a top flange 5 by a mounting and demounting mechanism 12 described later. The side wall portions 2A and 2C, which serve as the lateral wall portions when placed in horizontal posture, are detachable at its outside with carrying handles.

As viewed in FIGS. 6 and 7, the top flange 5 includes a flange portion 25 and a main unit portion 26. The top flange 25 is used as a member to be held by an arm portion (not shown) of the carriage device. The flange portion 25 is formed in almost a square flat shape. The flange portion 25 of the top flange 5 is used to be held by the arm portion of the carriage device for carrying the thin plate container 1 in a factory. The main unit portion 26 is used as a member to be attached to the container body 2 while supporting the flange portion 25. The main unit portion 26 is provided at its rear side with one member of the mounting and demounting mechanism 12 described later.

The side wall portion 2B of the container body 2 is provided at its center with the other member of the mounting and demounting mechanism 12, to be used for detaching the top flange 5. The mounting and demounting mechanism 12 is configured as viewed in FIGS. 4 and 5. Specifically, it includes a sliding support means 27, fitting means 28 and a guide rail 29.

The sliding support means 27 is used as a member for supporting the container body 2 and the top flange 5 so as to allow them to slide on each other. The sliding support means 27 includes a supporting portion 30 which is disposed on the container body 2 side and a sliding portion 31 which is disposed on the top flange 5 side and inserted into the supporting portion 30 from the proximal side to the distal side (the right side end to the left side end in FIG. 4). The supporting portion 30 includes two rails provided in parallel on the outside surface of the side wall 2B of the container body 2. These rail members have grooves which are open outward (in such direction that the two rail members turn away from each other). The sliding portion 31 includes rail members each disposed at the position corresponding to those of the supporting portion 30, on the main unit portion 26 of the top flange 5. These rail members have grooves which are open inward. The supporting portion 30 and the sliding portion 31 are laid out so that the space between the rails is narrow on the proximal side (right side in FIG. 4) and wide on the distal side. This facilitates the mating between the sliding portion 31 and the supporting portion 30.

The fitting means 28 is used as a member for securing the engagement between the container body 2 slidably supported by the sliding support means 27 and the top flange 5. The fitting means 28 includes fitting projections 33 disposed on the container body 2 and fitting pawls 34 disposed on top flange 5. The two fitting projections 33 are provided on the side wall portion 2B. The fitting projections 33 are each located at the center between the both ends of the two supporting portions 30. The respective fitting projections 33 serve to support the fitting pawls 34 while preventing them from displacing toward the proximal side (the right side in FIG. 4), with its surface facing the distal side (the left side in FIG. 4) serving as a vertical abutting surface.

The fitting pawls 34 are used as members to prevent the top flange 5 from falling off by securing engagement with the fitting projections 33. The two fitting pawls 34 are provided on the main unit portion 26 of the top flange 5. Specifically, a distal-side fitting pawl 34A and a proximal-side fitting pawl 34B are provided. The distal-side fitting pawl 34A includes an abutting portion 36 for abutting against the distal-side fitting projections 33 and a supporting bar portion 37 for supporting the abutting portion 36. The abutting portion 36 serves to support the top flange 5 while preventing it from displacing toward the proximal side, with its surface facing the proximal side serving as a vertical abutting surface to abut against the fitting projections 33. The supporting bar portion 37 is formed so as to extend to the container body 2 as well as the distal side.

The proximal-side fitting pawl 34B includes an abutting portion 38 for abutting against the fitting projections 33 on the proximal side and a supporting bar portion 39 for supporting the abutting portion 38. The abutting portion 38 serves to support the proximal-side fitting pawl 34B while preventing it from displacing toward the proximal side, with its surface facing the proximal side serving as a vertical abutting surface to abut against the fitting projections 33. The supporting bar portion 39 is formed so as to extend to the container body 2 as well as the proximal side. By the supporting bar 39, the abutting portion 38 is positioned on the container body 2 with respect to the base end portion of supporting bar portion 39. With this arrangement, if force causing the top flange 5 to fall off is applied, the abutting portion 38 is pressed against the fitting projections 33 deeply. This securely suppresses the disengagement between the abutting portion 38 and the fitting projections 33 even under a strong force applied to the relevant portion due to an impact, thereby preventing the top flange 5 from falling off, due to the counteraction of the supporting bar portion 39 (see FIGS. 8 and 9).

The guide rail 29 is used as a member for guiding sliding of the top flange 5 supported by the container 2 by means of the sliding supporting means 27 to position the protective cover in the direction perpendicular to the sliding direction. The guide rail 29 includes fitting rail portions 29A and fitted rail portions 29B. The fitting rail portions 29A include one rail member and disposed at two locations between the two supporting portions 30 on the side wall portion 2B of the container body 2. The fitted rail portions 29B include two rail members that catch the fitting rail portions 29A from both sides and disposed on the top flange 5 side that are opponent to the fitting rail portions 29A. The fitting rail portions 29A and the fitted rail portions 29B are positioned in parallel, respectively. With this arrangement, the fitting rail portions 29A fit with the fitted rail portions 29B and support the sliding of the top flange 5 from the proximal side to the distal side and vice versa, thereby helping easy mounting and demounting of the top flange 5 to and from the container body 2.

As viewed in FIGS. 1 to 3 and 10 to 16, the top flange 5 is detachable with a protective cover 41. The protective cover 41 serves as a top flange protective cover for a thin plate container, for protecting a package of the container when vacuum packed, by covering the entirety of the top flange 5. The protective cover 41 is formed in a square dish shape that covers the entirety of the flange portion 25 protruding outward, forming a square flat shape. The protective cover 41 is formed such that its height is highest at the center and smoothly decreases toward the circumferential edge. This prevents the profile of the protective cover from having sharp-edged portions.

The protective cover 41 is provided at its lower surface with abutting portions 42, fitting pawls 43 and handles 44.

The abutting portions 42 are used as members for abutting against each of the opponent two sides of the flange portion 25 on the top flange 5 to make positioning of the protective cover 41 in one direction. The abutting portions 42 are disposed at two opposing locations on the lower surface of the protective cover 41 separated the same space apart as that of the dimensions of the flange portion 25 on the top flange 5. The abutting portions 42 are each constructed as a flat resilient piece. Thus, when the protective cover 41 is attached to the flange portion 25 of the top flange 5, the two abutting portions 42 serve to catch the flange portion 25 between them to support it from both sides while bending themselves, so as to make positioning of the protective cover 41 with respect to the flange portion 25.

The fitting pawls 43 are used as members for abutting against the two sides of the flange portion 25 that are perpendicular to the abutting portions 42 to make positioning in another direction, and for fitting the two corresponding sides. The fitting pawls 43 are disposed at two opposing locations on the lower surface of the protective cover 41 separated the same space apart as that of the dimensions of the flange portion 25 on the top flange 5. The fitting pawls 43 are each constructed as a flat resilient piece. Thus, when the protective cover is attached to the flange portion 25 of the top flange 5, the two fitting pawls 43 serve to catch the flange portion 25 between them to support it from both sides while bending themselves, so as to make positioning of the protective cover 41 with respect to the flange portion 25. Moreover, the fitting pawls 43 each has a pawl portion 43A at their tip portions. These pawl portions 43A run around to the back side of the flange portion 25 to securely engage with the flange portion 25.

The protective cover 41 is provided with two slits 45 formed from the circumferential edge to both sides of the fitting pawls 43. These slits 45 facilitate easy bending of the fitting pawls 43.

The handles 44 are intended to be opened and closed by the operator's hands to open and close the fitting pawls 43. The handles 44 are located between the peripheral portion of the protective cover 41 defined by the two slits 45 and the corresponding fitting pawl 43. The handles 44 are constructed to have a space to allow the operator's hands to be inserted, between the peripheral portion of the protective cover 41 and the fitting pawl 43. The operator inserts both hands into the two handles 44 to open and close the fitting pawls 43.

[Operation]

The thin plate container 1 configured as described above is used in the following manner.

A container body 2 containing a plurality of semiconductor wafers is transported to a semiconductor manufacturing factory or the like, with its lid unit attached. The thin plate container 1 may be vacuum packed for transportation.

In such a case, the protective cover 41 is placed on and constrained to the flange portion 25 of the top flange 5. At this time, the abutting portions 42 and the fitting pawls 43 on the protective cover 41 abut against the respective sides of the flange portion 25, to make accurate positioning of the protective cover 41 with respect to the flange portion 25.

In this state, the operator pushes the protective cover 41 to fit it to the flange portion 25, or do the same while opening the handles 44 by both hands.

This makes the fitting pawls 43 abut against the peripheral portion of the flange portion 25, thereby constraining the protective cover 41 to the top flange 5.

In this state, the thin plate container 1 is enclosed within a package and air is vacuumed from the package to make it vacuum packed. Then the thin plate container 1 is transported.

After transportation, the package is cut open and removed and the container is take out while opening the handles 44 of the protective cover 41 with the hands.

Then the thin plate container 1 is transported to the manufacturing line with its top flange 5 held by the arm of a transport device.

[Effects]

Since, while a pair of abutting portions 42 and a pair of fitting pawls 43 on the protective cover 41 abut against each side of the flange portion 25 to make positioning of the protective cover 41 with respect to the top flange 5, the pair of fitting pawls 43 further engage with the flange portion 25 to constrain the protective cover 41 to the top flange 5, the protective cover 41 can be easily attached to the flange portion 25 of the top flange 5, thereby securely preventing the vacuum package from coming into contact with and being cut by a sharp edge of the top flange 5.

At this time, since the protective cover 41 can be easily mounted and demounted to the top flange 5, operation efficiency can also be improved during vacuum packing.

Since the handles enable the operator to easily open and close the fitting pawls 43 just by opening and closing the handles 44 by inserting both hands, the fitting pawls 43 can easily bend and engage with and disengage from the flange portion 25, thereby enabling the protective cover 41 to be easily mounted and demounted to and from the flange portion 25.

Since the top flange 5 is covered with the protective cover 41 when the thin plate container 1 is vacuum packed, and the profile of the outside surface of the protective cover 41 is formed to have a smooth slant, a vacuum package is prevented from directly coming into contact with the top flange 5 and the protective cover 41 having a smoothly-slanted profile is enclosed in the vacuum package, thereby securely preventing the vacuum package from being broken. This also enables the inside of the thin plate container 1 to be securely kept clean during transportation.

Variation Examples

(1) In the above-described embodiment, the abutting portions 42 and the fitting pawls 43 are formed in a flat shape. However, there may be provided fitting portions and fitted portions between the abutting portions 42 and fitting pawls 43 and the flange portion 25. In this case, V-grooves 25A serving as fitting portions (see FIGS. 6 and 7) are disposed on the flange portion 25 of the top flange 5. These V-grooves 25A are formed by cutting out the center of each side of the flange portion 25 in a shape of a V. The abutting portions 42 and the fitting pawls 43 of the protective cover 41 are provided with V-shape projections (not shown) serving as fitted portions that engage with the V-grooves 25A.

With this arrangement, when the abutting portions 42 and fitting pawls 43 on the protective cover 41 engage with the flange portion 25, the V-shape projections fit with the corresponding V-grooves 25A to make easy positioning of the protective cover 41 with respect to the flange portion 25. This facilitates attaching of the protective cover 41 to the flange 25.

(2) In accordance with the above-described embodiment, the protective cover 41 was formed in a square dish shape that covers the entirety of the flange portion 25 extruding outward in a square flat shape, but it may also be formed in a circular dish shape. That is, as viewed in FIG. 17, the protective cover 47, which is detachable to the top flange 5 disposed on the wall portion 2B making up the container body 2 of the thin plate container 1, may be formed in a circular dish shape. In this case, only the outside profile of the protective cover 47 may be formed in a circular shape while the abutting portions, fitting pawls and handles provided on the lower surface of the protective cover 47 may be formed in the same manner as the abutting portions 42, fitting pawls 43 and handles 44 of the protective cover 41 in accordance with the above-mentioned embodiment.

With this arrangement, the protective cover 47 formed in a circular dish shape is attached to the flange portion 25 of the top flange 5 that is formed in almost a square flat shape and can cover the sharp-edged portions. This allows the above-described protective cover 47 to be easily attached to the above-stated flange portion 25, thereby preventing a vacuum package from coming into contact with the sharp-edged portions of the top flange 5 and being broken.

The protective cover may also be formed in an oval shape, a pentagon shape or any polygonal shape with more than five sides and angles, other than the circular shape as viewed in FIG. 17. Such variations have the same operations and effect as those of the above-described embodiment. 

1. A top flange protective cover for a thin plate container detachable to the top flange which is provided on the thin plate container so as to protrude outward therefrom, comprising: an outside surface having no edges thereon; and a surface facing the top flange, including: a pair of abutting portions abutting against a flange portion of the top flange, for positioning in one direction; and a pair of fitting pawls abutting against the flange portion in one direction perpendicular to each of the abutting portions, for positioning in the other direction, wherein the protective cover is formed to cover the entire outside surface of the top flange when attached to the top flange.
 2. The top flange protective cover for a thin plate container of claim 1, wherein the protective cover is formed in a square dish shape which covers the entire flange portion according to the flange portion of the top flange.
 3. The top flange protective cover for a thin plate container of claim 1, wherein the protective cover is formed in a circular dish shape which covers the entire flange portion according to the top flange.
 4. The top flange protective cover for a thin plate container of claim 1, wherein two slits are formed from the circumferential edge to both sides of the fitting pawls to facilitate bending of the fitting pawls; and wherein handles are provided between each of the peripheral portions of the protective cover divided by the two slits and each fitting stopping pawl, for opening and closing the fitting pawls.
 5. A thin plate container having a top flange held by an arm of a carrier device, comprising: an outside surface having no edges thereon; and a surface facing the top flange, including: a pair of abutting portions abutting against a flange portion of the top flange, for positioning in one direction; and a pair of fitting pawls abutting against the flange portion in one direction perpendicular to each of the abutting portions, for positioning in the other direction, being formed to cover the entire outside surface of the top flange when attached to the top flange.
 6. The thin plate container of claim 5, wherein the flange portion of the top flange is formed in almost a square flat shape, and the top flange protective cover for a thin plate container is formed in a square dish shape which covers the entirety of the flange portion, and wherein fitting portions are provided on each of the four sides of the flange portion of the top flange, and fitted portions are provided at two locations at either one of or four locations at both of the pair of abutting portions and the pair of fitting pawls. 